ptp_measurement.h

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// Copyright 2024-2025 The Aerospace Corporation.
// This file is a part of SatCat5, licensed under CERN-OHL-W v2 or later.
 
#pragma once
 
#include <satcat5/ptp_header.h>
#include <satcat5/ptp_time.h>
 
// Cache-size parameter sets the maximum number of two-way
// PTP handshakes that can be in-flight at a given time.
#ifndef SATCAT5_PTP_CACHE_SIZE
#define SATCAT5_PTP_CACHE_SIZE 4
#endif
 
namespace satcat5 {
    namespace ptp {
        struct Measurement {
            satcat5::ptp::Header ref;
            satcat5::ptp::Time t1;      
            satcat5::ptp::Time t2;      
            satcat5::ptp::Time t3;      
            satcat5::ptp::Time t4;      
 
            // Explicitly declare default constructor and assignment methods.
            Measurement() = default;
            Measurement(const Measurement& t) = default;
            Measurement& operator=(const Measurement& t) = default;
 
            bool done() const;
 
            void log_to(satcat5::log::LogBuffer& wr) const;
 
            bool match(
                const satcat5::ptp::Header& hdr,
                const satcat5::ptp::PortId& port) const;
 
            satcat5::ptp::Time mean_path_delay() const;
            satcat5::ptp::Time mean_link_delay() const;
            satcat5::ptp::Time offset_from_master() const;
 
            void reset(const satcat5::ptp::Header& hdr);
        };
 
        constexpr satcat5::ptp::Measurement MEASUREMENT_NULL = {};
 
        class MeasurementCache {
        public:
            constexpr MeasurementCache()
                : m_next_wr(0), m_buff{} {}
 
            satcat5::ptp::Measurement* find(
                const satcat5::ptp::Header& hdr,
                const satcat5::ptp::PortId& port);
 
            inline satcat5::ptp::Measurement* find(
                const satcat5::ptp::Header& hdr)
                { return find(hdr, hdr.src_port); }
 
            satcat5::ptp::Measurement* push(
                const satcat5::ptp::Header& hdr);
 
        protected:
            unsigned m_next_wr;
            satcat5::ptp::Measurement m_buff[SATCAT5_PTP_CACHE_SIZE];
        };
    }
}